US 12,236,569 B2
System and method of welding workpiece by vision guided welding platform
Zongjie (Jason) Tao, Shanghai (CN); Dandan (Emily) Zhang, Shanghai (CN); and Roberto Francisco-Yi Lu, Bellevue, WA (US)
Assigned to TE Connectivity Solutions GmbH, Schaffhausen (CH); and Tyco Electronics (Shanghai) Co., Ltd., SwitzerlandShanghai (CN)
Filed by Tyco Electronics (Shanghai) Co. Ltd., Shanghai (CN); and TE Connectivity Services GmbH, Schaffhausen (CH)
Filed on Jan. 21, 2022, as Appl. No. 17/581,244.
Claims priority of application No. 202110087522.X (CN), filed on Jan. 22, 2021.
Prior Publication US 2022/0237768 A1, Jul. 28, 2022
Int. Cl. G06T 7/80 (2017.01); B23K 26/03 (2006.01); B23K 26/21 (2014.01); B23K 37/04 (2006.01); G06T 1/00 (2006.01); G06T 7/00 (2017.01); G06T 7/60 (2017.01); G06T 7/70 (2017.01); H04N 23/67 (2023.01); G01N 21/88 (2006.01)
CPC G06T 7/0004 (2013.01) [B23K 26/032 (2013.01); B23K 26/21 (2015.10); B23K 37/04 (2013.01); G06T 1/0014 (2013.01); G06T 7/60 (2013.01); G06T 7/70 (2017.01); G06T 7/80 (2017.01); H04N 23/67 (2023.01); G01N 21/8851 (2013.01); G01N 2203/0296 (2013.01); G06T 2207/30152 (2013.01); G06T 2207/30164 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A system for welding a workpiece, comprising:
a vision guided welding platform, including:
a welding tool;
a camera visually guiding the movement of the welding tool from a start point to an end point on the workpiece; and
a control system operatively connected to the welding tool and the camera, the control system responsive to a set of program instructions for:
obtaining a surface image of the workpiece in a field of view of the camera;
determining a current focal length of the camera;
determining a corrected pixel length of a pixel in the surface image corresponding to the determined current focal length based on the determined current focal length and a predetermined focal length-corrected pixel length correspondence relationship, the predetermined focal length-corrected pixel length determined by:
determining the focal length-corrected pixel length correspondence relationship according to a calibration sample and a calibration scale provided on the calibration sample;
adjusting the focal length of the camera so that the camera focuses on a surface of the calibration sample with a plurality of different focal lengths, and two known calibration points are located in the field of view of the camera, and obtaining the surface image of the calibration sample in the field of view of the camera;
determining the pixel length of the pixel in the surface image of the calibration sample at each focal length based on a known spacing between the two known calibration points of the calibration scale; and
establishing the focal length-corrected pixel length correspondence relationship by taking the determined pixel lengths as the corrected pixel lengths respectively corresponding to different focal lengths;
determining a number of pixels in the surface image between the start point and the end point of each movement of the welding tool; and
determining a distance between the start point and the end point based on the determined corrected pixel length and the number of pixels.